Controlling system



Dec. 22, 1925.

c. W. WYMAN CONTROLLING SYSTEM Filed May 14. 1923 Patented Dec. 22, 1925.

umrtzn CHARLES W. WYMAN, 0F CLAEEMQN'I, NEW H I%C IPS1FIFRE, J-LSiiIGNQB, T0 SULLIVAN MACHINERY COMPANY, 13. GOEFQRATIQN Q13 MASS'aAGHUSETTS.

CONTROLLING SY$TEEL Application. filed May 1 1-,

To all whom it may concern:

Be it known that I, CHARLES W. \VYMAN, a citizen of the United States, residing at Claremont, in the county of Sullivan and State of New Hampshire, have invented certain new and useful Improvements in Controlling Systems, of which the following is a full, clear, and exact specification.

My invention relates to controlling systems, and more particularly to controlling systems for electrically operated mining mechanisms.

It is found in many mines that there is combustible gas released during the process of cutting and accordingly it is important that at the working face there shall he absolutely no possible chance for the to have access to a spark or flame. Accordingly, in mines of this type it is customary to use alternating current motors where the sparking resulting from commutation is avoided and to very carefully enclose and seal all electric controlling mechanism upon the machines. Circuit making and breaking devices are still present upon the machine, however. It is obvious that this system could be substantially improved by the elimination from the mining machine proper of all mechanism which requires the making and breaking of electric circuits.

It is the object of my invention to provide an improved controlling system in which, while controlling mechanism is arranged upon the mining machine whereby the latter may be very readily and conveniently controlled, all circuit making and breaking mechanism is disposed at a very material distance from the machine, and so from the working face, and out in, or near, an entry Where the ventilation is better and the probability of the presence of explosive mixtures is less.

In the accompanying drawings I have shown for purposes of illustration two forms which my invention may assume in practice.

In these drawings,

Fig. 1 is a plan view of a portion of a mine showing a mining machine at work and the disposition of the controlling mechanism.

Fig. 2 is a diagrammatic view of the circuits of one illustrative form of this controlling mechanism.

, from the line 12 a wire 23 leads to a 1823. Serial No. 838,922.

Fig. 3 is a view of a modified. form of construction.

it will be observed that the mining machine 1 is engaged in making a longwall cut 52- in an extended face and that the machine is supplied with current through a flexible cable 1 which extends from the face back to a controlling mechanism or box 5 which is arranged near the entry 6. It will be further noted that the mechanism 5 is herein shown as connected by a short cable 7 controlled by a three-pole switch 8 with the power lines strung around the mine, these power lines being indicated at 9, and being a three-phase distribution system. it will be understood that the three-pole switch may be enclosed in the same casing with the mechanism 5 if desired.

Now noting 2, l have shown at 11, 12 and 13 three wires which are arranged within the cable 7 and lead from the power lines 9 into the box 5. 'fithin the box 5 these three circuits controlled by a three-pole switch 14 which is shown only diagrammatically and which is herein of the knife blade type and operated by a rotatable shaft 15. The Wi res 11, 12 and 13 are arranged within the cable iand lead directly to the windings of the motor 16 upon the mining ma chine 1, here being no breal in the circuit whatever between the motor windings and the box 5. For the purpose of operating the switch 14: means is provided for oscillating the shaft 15 arms .15 which carry a pair of iron plungers or armatures 17 and 18 with which magnet coils 19 and 20 are respectively adapted to cooperate. it will be noted that these coils are arranged in. series with other hollow coils 21 and 22 respectively in such manner as to form balanced circuit connected to the lines 12 and 13, it being observed that point between the coils 19 and 20 and that the coils 10 and 21 are connected by Way of a wire 94 with the line 13 while the coils 20 and 22 are likewise connected with this wire. By properly designing the coils 19, 20, 21 and 22, the circuit may be exactly balanced so that the current flow through the coils 19 and 20 is equal and so that the magnetic fields produced by them are equal and as a result it-will be possible by varying the current flow through the coils 19 and 20 to comprising a transverse pair of 7c it Is at the working race. A

cause theplungers or cores 1.7 and 18 to be differently attracted. and so to operate the switch operating shaft For the purpose of effecting this ditlerent energization of the coils l9 and 20, it will be observed that l have arranged a pair of iron cores 25 and 26 and mounted them upon swinging arm 27 which by means of a handle may moved from its mid-position in which it is normally held by spring 29 in such manner as to cause one of the cores 2? to enter its cor esponding coil 21 or and so produce an ihductive reactance which will cut down rery largely the flow through. the coil and so througgl'i the magnet coil 19 or 20 which is to be in circuit with it.

From the d scription so far given the mode of operation of this mechanism will be readily understood. Assume that the mining machine is ready to maize a cut and that he main line switch 8 having been closed, the operatorby a manipulation of the handle :48 can swing the lerer 2.7 in a manner to cause the core to enter the coil Ql. a result of the rethrough actance produced, the current lie the circuit 12, 28, 19, 21, 24c, 13 wi be greatly reduced, while the current low through the winding; 20 will not be substantially diminished. As a result the cores 1? and 18 will no longer be equally attracted, but the core 18 will be much more strongly attracted. and will drawn down by the magnet 20 in a manner to close the circuit and thereby start the motor 16. V] hen it is desired to interrupt the opera ion of the motor, this may be done by swinging the lever 28 in the opposite lirection and weakening the field oi the coil 20 while restoring the field of the coil 19 to original strength. It will be apparent that it is readily possible to substitute for the mechanism 14 a type of switch which will first connect the motor windii' in star and then in delta and then return thci i to mid-position, suitable latch mechanism for accorn alishing this sequence of events being employed.

It will also be evident that any suitable detent means may be used to hold the lever 28 in desired positions and that spring means for returning the controller id to off position may be'usec if desired. Moreover, it will be ap arent that the cores 25 and 26 may be so supported to normally project into the coils 21 and 22, so that the reactance in these coils will diminish the current flow through the control mechanism, and that operation of the lever 28 may then be caused to withdraw one core while projecting the other further into its cooperating coil and so to effect a variation in the pulls exerted by the coils 19 and 20. It will be clear also that a single magnet coil might be used to close a switch and a spring to open it.

In the form shown in Fi 3 the mode of 0 g (in) operation is generally the same, but instead of having the coils 19 and 20 directly operate the controller as in Fig. 2, the coils ll) and 25) perate a relay switch 30 which closes circrfJ-s through one or the other oi the coils 31 and which operate the armatures l7 and 18 In this form therefore the current flow through the coils l9 and 20 may be very small while yet permitting the operation or": the controller. From the description of the various forms of my mechanism, it will be observe that there is no making" nor breaking of any circuit upon the mining machine and a result, with the 31C type motor, there is nopossible cause of sparking at the macl inc and all sparking and arcing; that takes place occurs near the entrance to the working; tace, or even clear out in the entry that location preferred, and so the mechanism is absolutely and no danger can be created by taking off cover plates from the machine or anything of that variety. It will be understood that space relations are not shown with mathematical nicety in- F 2 and 3, and that in practice the shaft will be perpendicular to the plane of the axes of coils i9, 20 or 31, 32.

ll hile I have in this application specifically described two forms which my invention may assume in practice, it will be understood that these torms of the same are shown for purposes of illustration and that the invention may be modified and embo in various other forms without departing "from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a system of devices for controlling the transmission of power to an electric motor driven mining machine. a plural-part set of motor control devices. one part being mounted permanently on the mining; mach ne and the other be; connectible with a power circuit and adapted to remain at a. (llbtitl'lCQ from the minim machine while the latter is ci'itting, said second mentioned part iomprising all circuit making and bre g devices, and said first mentioned part constituting controlling means for said circuit making and breaking devices.

2. in a system oi devices for controlling the transmission Oil power to the electric driving motor of a mechanism which is caused to undergo motion of translation by a driving motor which moves therewith, a plural-part set of motor control devices, one part being mounted permanently on said mechanism and the other being connectible with a power circuit and adapted to remain at a distance tromsaid mechanism while operative, said second mentioned part comprising all circuit making and breaking devices, and said first mentioned part constituting controlling means for said circuit making and breaking devices.

3. In a system of devices for controlling the transmission of power to an electric motor driven mining machine, a plural-part set of motor control devices, one part being mounted permanently on the mining machine and the other being connectible with a power circuit and adapted to remain at a distance from the mining machine while the latter is cutting, said parts being connected only by flexible current conducting means and said second mentioned part comprising all circuit making and breaking devices, and said first mentioned part constituting controlling means for said circuit making and breaking devices.

4. In a system of devices for controlling the transmission of power to an electric motor driven mining machine, 'a plural-part set of motor control devices, one part being mounted permanently on the mining machine and the other being connectible with a power circuit and being adapted to remain at a distance from the working face, said parts being connected by a flexible cable comprising motor power lines and controlling circuit wires, said second mentioned part comprising circuit making and breaking means controlling said power lines and electro-magnetic control means for said circuit making and breaking means connected to said controlling circuit wires, and said first mentioned part comprising means for controlling the current flow in said controlling circuit wires without interrupting it.

5. In a system of devices for controlling the transmission of power to an electric motor driven mining machine, a plural-part set of motor control devices, one part being mounted permanently on the mining machine and the other being connectible with a power circuit and being adapted to remain at a distance from the working face, said parts being connected by a flexible cable comprising motor power lines and controlling circuit wires, said second mentioned part comprising circuit making and break ing means controlling said power lines and electro-magnetic control means for said circuit making and breaking means connected to said controlling circuit Wires, and said first mentioned part comprising means for controlling the current fiow in said controlling circuit wires without interrupting it, comprising means for varying by infinitesimal amounts the current flow in said controlling circuit wires.

6. In a controlling system, a solenoid, an armature movable relative to said solenoid, a second solenoid connected in series with said first mentioned solenoid, said solenoids being connected to an alternating current circuit, and means for controlling the current flow in said first mentioned solenoid to vary the magnetic field thereof including a core of permeable material movable relative to said second mentioned solenoid, said armature and core being substantially free from the magnetic influence of said solenoids when said system is in a neutral state.

7. In a controlling system, a controlling element, a solenoid whose magnetic field controls the movement of said element, a second solenoid, said solenoids being connected in series across AC lines, and means cooperating with said second solenoid to produce an inductive reactance to thereby control the strength of the field of said first mentioned solenoid, said system being substantially in a balanced state when the reactance of said solenoids is at a minimum.

8. In an electric system including an electrical device to be controlled, means for controlling the same comprising a magnet coil, a second coil arranged in series with said magnet coil, and means cooperating with said second mentioned coil for varying the inductive reactance thereof to control the strength of the field of said first mentioned coil, said device being inoperative when the reactance of said second coil is at a minimum.

9. In a controlling system, a pair of magnet coils connected together at one end thereof, a pair of controlling coils connected together at one end thereof, the other end of one of said magnet coils being connected to the other end of one of said controlling coils and the other end of the other of said magnet coils being connected to the other end of the other of said controlling coils, a connection from an AC circuit to the interconnected ends of said magnet coils, a connection from an AC circuit to the interconnected ends of said controlling coils, means controlled by said magnet coils, and means including a pair of permeable cores adjustable relative to said controlling coils for controlling the current flow through said magnet coils, said controlling coils also be ing adapted to simultaneously have a'minimum of reactance.

In testimony whereof I aflix my signature.

CHARLES W. WYMAN. 

